Extendable swing arm assembly for a treadmill

ABSTRACT

An extendable swing arm assembly for a treadmill having an upright frame, a base frame, a front support, and a rear support. The extendable swing arm assembly includes an angled support with an extension arm, a swing arm with a handle, a mounting yoke with a supporting rod, and a resistance element. The middle part of the angled support is pivotally attached to the mounting yoke. The swing arm is inserted from an open end of the angled support thereinto and preloaded by a spring such that the swing arm moves in an extended and a retracted position. The supporting rod at the bottom of the mounting yoke is inserted into the mounting tubes, and the resistance element is pivoted at the rear end of the extension arm and a base of the supporting rod.

BACKGROUND OF THE INVENTION

1. Fields of the Invention

The present invention relates to a rocker arm for an electric treadmill, and more particularly, to a device which adjusts to the curvature of the natural swing of the arms of the treadmill's user and, therefore, makes a synchronic movement.

2. Description of the Prior Art

Many commercially available electric treadmills are provided with two rocker arms swingable backward and forward along with both arms of the operator and fitted to an upright frame, a base frame or a handrail. Even, a resistant element is added to the rocker arms so that the operator can exercise the arm muscle while walking. These disclosures can be seen in U.S. Pat. Nos. 5,460,586, 5,527,245, 5,688,209, 5,431,612, 5,207,622, 5,860,894, 5,709,632, etc.

The rocker arms of the above-mentioned disclosures are swung in parabolic form since they are composed of a single element in combination with a single pivotal point. This point is evidently contrary to the natural exercise mode of the human body so that the user feels uncomfortably during the exercise session when he holds the rocker arms.

SUMMARY OF THE INVENTION

It is a primary object of the present invention to remove the above-mentioned drawbacks and to provide a rocker arm for an electric treadmill whose movement path corresponds to the natural swing curvature of the user's hands in order to reach the expected exercise effect.

It's another object of the present invention to provide a rocker arm for an electric treadmill which is provided with a resistance element (e.g. balance weight, small-type hydraulic cylinder unit, etc.) in order to make full use of the rocker arms.

BRIEF DESCRIPTION OF THE DRAWINGS

The accomplishment of this and other objects of the invention will become apparent from the following description and its accompanying drawings of which:

FIG. 1 is a schematic drawing of a preferred embodiment of the invention;

FIG. 2 is a schematic drawing of an extendable swing arm assembly for a treadmill;

FIG. 3 is a schematic drawing of the extendable swing arm assembly with its swing arm in extended position;

FIG. 4 is a perspective exploded view of an angled support in accordance with the invention; and

FIG. 5 is a schematic drawing of another preferred embodiment of the extendable swing arm assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1, 2 and 3, an extendable swing arm assembly for a treadmill 10 includes an upright frame 12, a base frame 14, a front support 16 and a rear support 18. The upright frame 12 has an electronic console 20 and two arm supports 22 at both sides thereof. A running band surrounds the base frame 14 for an in-place rotation. In addition, the treadmill 10 has two mounting tubes 24 in each of which one extendable swing arm assembly 30 is received. Both hands of the operator can hold on the extendable swing arm assemblies 30 for a forward and backward movement. Both extendable swing arm assemblies 30 have the same configuration and each include an angled support 31 with an extension arm 311, a swing arm 32 with a handle 321, a mounting yoke 33 with a supporting rod 331, and a resistance element 34. The middle part of the angled support 31 is pivotally attached to the mounting yoke 33. The swing arm 32 is inserted from an open end of the angled support 31 into the angled support 31 and preloaded by a spring 312 so that the swing arm 32 moves in an extended and retracted position. Moreover, the supporting rod 331 at the bottom of the mounting yoke 33 is inserted into the mounting tubes 24. The resistance element 34 is pivoted at the rear end of the extension arm 311 and a base 332 of the supporting rod 331.

The above described mounting tube 24 is installed at the internal side of the upright frame 12 of the treadmill 10. So it can determine the position of the extendable swing arm assembly 30 and have the pivotal movement in proper direction.

By use of the swinging design of the angled support 31 and the swing arm 32, the movement path of the extendable swing arm assembly 30 corresponds to the swinging curvature of user's arms. So the expected effect is reached.

In order to prevent the swing arm 32 from drawing out of the angled support 31, a metal cap 35 is installed inside the near end of the angled support 31.

When the swing arm 32 is moved to bring the basic angled support 31 in rotation, a tappet 341 of the resistance element 34 will be extended. In this way, the movement of the operator will be hindered to reach the effect of training his muscles. Meanwhile, the spring 312 inside the angled support 31 is pulled in an extended position. When the force acting on the swinging arm 32 disappears, the spring 312 will return to its original state and is located within the angled support 31.

The resistance element 34 is constructed as spring, hydraulic cylinder, preloaded hydraulic cylinder, etc. with the resisting function.

Also, the invention utilizes the swing arm 32 or the handle 321. One or more heavy objects can hang on them (not shown). So it can bring an additional resistance to the movement so as to reach a better training effect on the muscle.

In order to ensure the proper pivoting action between the mounting yoke 33 and the resistance element 34, a bearing 26 can be installed between them.

As shown in FIG. 4, under the condition that the movement of the swing arm 32 won't be influenced, a screw hole 313 is provided in a proper position of the angled support 31. By use of an adjusting screw 40 with an air-guiding slot 41, different air flow will cause different air pressure. (The air flow of the air-guiding slot 41 will change correspondingly, if the screwing depth of the adjusting screw 40 is altered.) So the operator can adjust the drawing resistance between the swing arm 32 and the angled support 31 freely.

As shown in FIG. 5, under the condition that the moving space of the operator is not restricted, the resistance element 34 can be shifted to one side near the operator. But it has the same exercise effect. This design features that the resistance is created only when the resistance element 34 is pressed.

Many changes and modifications in the above-described embodiments of the invention can, of course, be carried out without departing from the scope thereof. Accordingly, to promote the progress in science and the useful arts, the invention is disclosed and is intended to be limited only by the scope of the appended claims. 

1. An extendable swing arm assembly for a treadmill having an upright frame, a base frame, a front support, and a rear support, the upright frame having an electronic console and two arm supports at both sides thereof, a running band surrounding the base frame for an in-place rotation, the treadmill having two mounting tubes in each of which one of two extendable swing arm assemblies is received so that both hands of the operator can hold on the extendable swing arm assemblies for a forward and backward movement, the extendable swing arm assembly comprising an angled support with an extension arm, a swing arm with a handle, a mounting yoke with a supporting rod, and a resistance element, a middle part of the angled support being pivotally attached to the mounting yoke, the swing arm being inserted from an open end of the angled support thereinto and preloaded by a spring so that the swing arm moves in an extended and a retracted position, the supporting rod at the bottom of the mounting yoke being inserted into the mounting tubes, the resistance element being pivoted at the rear end of the extension arm and a base of the supporting rod.
 2. The extendable swing arm assembly for a treadmill as claimed in claim 1 wherein at least one weight is hung on the handle of the swing arm.
 3. The extendable swing arm assembly for a treadmill as claimed in claim 1 wherein the angled support is provided with a screw hole in which an adjusting screw with an air-guiding slot is inserted for adjusting the movement resistance between the swing arm and the angled support. 